Refer to the exhibit. The 130.130.130.0/24 route shows in the R2 routing table but is getting filtering toward R3. Which action resolves the issue?
Refer to the exhibit. The 130.130.130.0/24 route shows in the R2 routing table but is getting filtering toward R3. Which action resolves the issue?
The issue is caused by IGP synchronization, a rule that prevents BGP from advertising routes learned from an iBGP neighbor to an eBGP neighbor unless those routes are present in the IGP. This is done to ensure that all routers within the AS know about the route before it is advertised externally. To resolve the issue, IGP synchronization must be disabled on R2, allowing BGP to advertise the 130.130.130.0/24 route from its iBGP neighbor (R1) to its eBGP neighbor (R3).
The answer is D https://www.cisco.com/c/en/us/support/docs/ip/border-gateway-protocol-bgp/19345-bgp-noad.html Scroll down to the "Unable to Announce iBGP-Learned Routes" section for the explaination.
I did and it is actually this diagram hahaha!
BGP synchronization is an old rule from the days when we didn’t run IBGP on all routers within a transit AS. In short, BGP will not advertise something that it learns from an IBGP neighbor to an EBGP neighbor if the prefix can’t be validated in its IGP.
After some reading I agree, you should DISABLE IGP synchronistation requirement using "no synchronization" under the "router bgp ..."
note "no synchronistation" is actually the default